A dense blanket of fog has enveloped Delhi and neighboring areas in northern India, causing travel delays and chaos.

According to news agency PTI, more than 100 flights were delayed at Delhi airport on Friday morning. Dozens of trains have also been rescheduled or are delayed.

The India Meteorological Department has said that foggy conditions are likely to continue in the next few days.

This time of year, Delhi and other parts of northern India often experience dense fog as the region battles a severe cold wave.

Photos and videos showed several cities shrouded in thick fog and haze.

According to the India Meteorological Department (IMD), around nine airports, including Delhi, had zero visibility on Friday morning.

Delhi Airport has issued an alert to passengers warning them of significant delays.

“While landings and take-offs continue at Delhi Airport, flights that are not CAT III compliant may be impacted,” the airport said in a statement, referring to the radar system that allows automatic landings in very low visibility conditions.

Several airlines have also issued statements urging travelers to check flight schedules before planning their trip.

IMD considers fog to be “dense” when visibility falls below 200 m and “very dense” when visibility falls below 50 m.

The weather department said Delhi may experience light to moderate rainfall on January 6, which is likely to bring temperatures down further.

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